Related papers: Electron Correlations in Molecular Systems
Quantum transitions between the Mott insulator and metals by controlling filling in two-dimensional square lattice are characterized by a large dynamical exponent $z=4$ where the origin of unusual metallic properties near the Mott insulator…
MgB_2 is considered as a binary system with 2D electrons. The classic BCS theory is applied to this system. The transition temperature is found to be relatively high, because 2D electrons are more capable of moving with the atoms, on top of…
In this review we recapitulate the basic features of the flat-band spin systems and briefly summarize earlier studies in the field. Main emphasis is made on recent developments which include results for both spin and electron flat-band…
Electron-phonon-driven charge density waves can in some circumstances allow electronic correlations to become predominant, driving a system into a Mott insulating state. New insights into both the Mott state and preceding charge density…
We investigate superconductivity emerging in the photodoped Mott insulating Hubbard model using steady-state dynamical mean-field theory implemented on the real-frequency axis. By employing high-order strong-coupling impurity solvers, we…
We study the transfer of spectral weight in the photoemission and optical spectra of strongly correlated electron systems. Within the LISA, that becomes exact in the limit of large lattice coordination, we consider and compare two models of…
Several useful thermodynamic relations are derived for metal-insulator transitions, as generalizations of the Clausius-Clapeyron and Eherenfest theorems. These relations hold in any spatial dimensions and at any temperatures. First, they…
The electronic structure of CrO_2 is critically discussed in terms of the relation of existing experimental data and well converged LSDA and GGA calculations of the electronic structure and transport properties of this half metal magnet,…
Density functional theory provides the most widespread framework for the realistic description of the electronic structure of solids, but the description of strongly-correlated systems has remained so far elusive. Here we consider a…
The electron correlations in narrow energy bands are examined in framework of the Hubbard model. The single-particle Green function and energy spectrum are obtained in paramagnetic state at half-filling by means of new two-pole…
We investigate the emergence of ferromagnetism in the two-dimensional metal-halide CoBr$_2$, with a special focus on the role of electronic correlations. The calculated phonon spectrum shows that the system is thermodynamically stable…
Attosecond spectroscopy of materials has provided invaluable insight into light-driven coherent electron dynamics. However, attosecond spectroscopies have so far been focused on weakly-correlated materials. As a result, the behavior of…
Motivated by recent experiments realizing correlated phenomena and superconductivity in 2D van der Waals devices, we consider the general problem of whether correlation effects may be enhanced by modifying band structure while keeping a…
We investigated optical absorption coefficient spectra of an epitaxial VO2 film in wide photon energy (0.5 - 5.0 eV) and temperature (100 - 380 K) regions. In its insulating phase, we observed two d-d transition peaks around 1.3 eV and 2.7…
The effective attractive interaction between electrons, mediated by electron-phonon coupling, is a well-established mechanism of conventional superconductivity. In metals exhibiting a Fermi surface, the critical temperature of…
The Roth's two-pole approximation has been used by the present authors to study the effects of the hybridization in the superconducting properties of a strongly correlated electron system. The model used is the extended Hubbard model which…
We study a multi-band Hubbard model in its orbital selective Mott phase, in which localized electrons in a narrow band coexist with itinerant electrons in a wide band. The low-energy physics of this phase is shown to be closely related to…
Correlation effects on electron transport through a system of T-shaped double-dots are investigated, for which only one of the dots is directly connected to the leads. We evaluate the local density of states and the conductance by means of…
Stable organic radicals integrated into molecular junctions represent a practical realization of the single-orbital Anderson impurity model. Motivated by recent experiments for perchlorotriphenylmethyl (PTM) molecules contacted to gold…
One of the central questions about the iron pnictides concerns the extent to which their electrons are strongly correlated. Here we address this issue through the phenomenology of the charge transport and dynamics, single-electron…